1.there isnt a pixl shaped like a hand, i think you mean thoreau, the pixl that gives you the grab ability
2. the bridge in what level? if its in level 1-2, then you dont use thoreau, you go through a pipe then talk to one of the bridge brothers in their houses, they will have you answer a question and then fix the bridge for you
3. if not, then what bridge?

Go to the door that is before the Witchit guy, go inside, flip then go down the tunnel once you are in there flip again to get pass the Big blue blocks, then open the door. Now once you are inside you can't see anything but a Transparent star shape to be able to see the hidden door just point your wii remote to the screen and press the button on the bottom of remote and hold it that will enable the butterly and then you'll be able to see the door appear. once the door appears go inside to unlock the Hand pixl. You will get locked inside but flip again to get out and open the chest to unlock the hand pixl after that you will have to grab the white block next to the chest and throw the block UP to hit the Blue block to unlock the door and get out. After all that go back to the witch it guy and he will call the guy from the bridge to tell him its ok to build bridge for you. Go back to the guy and he will build bridge for you. That's it level completed